| /* | 
 |  * Copyright (C) 1999 Lars Knoll (knoll@kde.org) | 
 |  *           (C) 1999 Antti Koivisto (koivisto@kde.org) | 
 |  *           (C) 2001 Dirk Mueller (mueller@kde.org) | 
 |  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org) | 
 |  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved. | 
 |  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/) | 
 |  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies) | 
 |  * Copyright (C) 2013 Google Inc. All rights reserved. | 
 |  * | 
 |  * This library is free software; you can redistribute it and/or | 
 |  * modify it under the terms of the GNU Library General Public | 
 |  * License as published by the Free Software Foundation; either | 
 |  * version 2 of the License, or (at your option) any later version. | 
 |  * | 
 |  * This library is distributed in the hope that it will be useful, | 
 |  * but WITHOUT ANY WARRANTY; without even the implied warranty of | 
 |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU | 
 |  * Library General Public License for more details. | 
 |  * | 
 |  * You should have received a copy of the GNU Library General Public License | 
 |  * along with this library; see the file COPYING.LIB.  If not, write to | 
 |  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, | 
 |  * Boston, MA 02110-1301, USA. | 
 |  */ | 
 |  | 
 | #include "config.h" | 
 | #include "core/dom/StyleSheetCollection.h" | 
 |  | 
 | #include "HTMLNames.h" | 
 | #include "SVGNames.h" | 
 | #include "core/css/CSSStyleSheet.h" | 
 | #include "core/css/StyleInvalidationAnalysis.h" | 
 | #include "core/css/StyleSheetContents.h" | 
 | #include "core/css/resolver/StyleResolver.h" | 
 | #include "core/dom/Document.h" | 
 | #include "core/dom/DocumentStyleSheetCollection.h" | 
 | #include "core/dom/Element.h" | 
 | #include "core/dom/ProcessingInstruction.h" | 
 | #include "core/html/HTMLIFrameElement.h" | 
 | #include "core/html/HTMLLinkElement.h" | 
 | #include "core/html/HTMLStyleElement.h" | 
 | #include "core/page/Page.h" | 
 | #include "core/page/PageGroup.h" | 
 | #include "core/page/Settings.h" | 
 | #include "core/page/UserContentURLPattern.h" | 
 | #include "core/svg/SVGStyleElement.h" | 
 |  | 
 | namespace WebCore { | 
 |  | 
 | using namespace HTMLNames; | 
 |  | 
 | StyleSheetCollection::StyleSheetCollection(TreeScope* treeScope) | 
 |     : m_treeScope(treeScope) | 
 |     , m_hadActiveLoadingStylesheet(false) | 
 | { | 
 | } | 
 |  | 
 | void StyleSheetCollection::addStyleSheetCandidateNode(Node* node, bool createdByParser) | 
 | { | 
 |     if (!node->inDocument()) | 
 |         return; | 
 |  | 
 |     // Until the <body> exists, we have no choice but to compare document positions, | 
 |     // since styles outside of the body and head continue to be shunted into the head | 
 |     // (and thus can shift to end up before dynamically added DOM content that is also | 
 |     // outside the body). | 
 |     if (createdByParser && document()->body()) | 
 |         m_styleSheetCandidateNodes.parserAdd(node); | 
 |     else | 
 |         m_styleSheetCandidateNodes.add(node); | 
 |  | 
 |     if (!isHTMLStyleElement(node)) | 
 |         return; | 
 |  | 
 |     ContainerNode* scopingNode = toHTMLStyleElement(node)->scopingNode(); | 
 |     if (!isTreeScopeRoot(scopingNode)) | 
 |         m_scopingNodesForStyleScoped.add(scopingNode); | 
 | } | 
 |  | 
 | void StyleSheetCollection::removeStyleSheetCandidateNode(Node* node, ContainerNode* scopingNode) | 
 | { | 
 |     m_styleSheetCandidateNodes.remove(node); | 
 |  | 
 |     if (!isTreeScopeRoot(scopingNode)) | 
 |         m_scopingNodesForStyleScoped.remove(scopingNode); | 
 | } | 
 |  | 
 | void StyleSheetCollection::collectStyleSheets(DocumentStyleSheetCollection* collections, Vector<RefPtr<StyleSheet> >& styleSheets, Vector<RefPtr<CSSStyleSheet> >& activeSheets) | 
 | { | 
 |     if (document()->settings() && !document()->settings()->authorAndUserStylesEnabled()) | 
 |         return; | 
 |  | 
 |     DocumentOrderedList::iterator begin = m_styleSheetCandidateNodes.begin(); | 
 |     DocumentOrderedList::iterator end = m_styleSheetCandidateNodes.end(); | 
 |     for (DocumentOrderedList::iterator it = begin; it != end; ++it) { | 
 |         Node* n = *it; | 
 |         StyleSheet* sheet = 0; | 
 |         CSSStyleSheet* activeSheet = 0; | 
 |         if (n->nodeType() == Node::PROCESSING_INSTRUCTION_NODE && !document()->isHTMLDocument()) { | 
 |             // Processing instruction (XML documents only). | 
 |             // We don't support linking to embedded CSS stylesheets, see <https://bugs.webkit.org/show_bug.cgi?id=49281> for discussion. | 
 |             ProcessingInstruction* pi = static_cast<ProcessingInstruction*>(n); | 
 |             // Don't apply XSL transforms to already transformed documents -- <rdar://problem/4132806> | 
 |             if (pi->isXSL() && !document()->transformSourceDocument()) { | 
 |                 // Don't apply XSL transforms until loading is finished. | 
 |                 if (!document()->parsing() && !pi->isLoading()) | 
 |                     document()->applyXSLTransform(pi); | 
 |                 return; | 
 |             } | 
 |             sheet = pi->sheet(); | 
 |             if (sheet && !sheet->disabled() && sheet->isCSSStyleSheet()) | 
 |                 activeSheet = static_cast<CSSStyleSheet*>(sheet); | 
 |         } else if ((n->isHTMLElement() && (n->hasTagName(linkTag) || n->hasTagName(styleTag))) || (n->isSVGElement() && n->hasTagName(SVGNames::styleTag))) { | 
 |             Element* e = toElement(n); | 
 |             AtomicString title = e->getAttribute(titleAttr); | 
 |             bool enabledViaScript = false; | 
 |             if (e->hasLocalName(linkTag)) { | 
 |                 // <LINK> element | 
 |                 HTMLLinkElement* linkElement = toHTMLLinkElement(n); | 
 |                 enabledViaScript = linkElement->isEnabledViaScript(); | 
 |                 if (!linkElement->isDisabled() && linkElement->styleSheetIsLoading()) { | 
 |                     // it is loading but we should still decide which style sheet set to use | 
 |                     if (!enabledViaScript && !title.isEmpty() && collections->preferredStylesheetSetName().isEmpty()) { | 
 |                         const AtomicString& rel = e->getAttribute(relAttr); | 
 |                         if (!rel.contains("alternate")) { | 
 |                             collections->setPreferredStylesheetSetName(title); | 
 |                             collections->setSelectedStylesheetSetName(title); | 
 |                         } | 
 |                     } | 
 |  | 
 |                     continue; | 
 |                 } | 
 |                 sheet = linkElement->sheet(); | 
 |                 if (!sheet) | 
 |                     title = nullAtom; | 
 |             } else if (n->isSVGElement() && n->hasTagName(SVGNames::styleTag)) { | 
 |                 sheet = static_cast<SVGStyleElement*>(n)->sheet(); | 
 |             } else { | 
 |                 sheet = static_cast<HTMLStyleElement*>(n)->sheet(); | 
 |             } | 
 |  | 
 |             if (sheet && !sheet->disabled() && sheet->isCSSStyleSheet()) | 
 |                 activeSheet = static_cast<CSSStyleSheet*>(sheet); | 
 |  | 
 |             // Check to see if this sheet belongs to a styleset | 
 |             // (thus making it PREFERRED or ALTERNATE rather than | 
 |             // PERSISTENT). | 
 |             AtomicString rel = e->getAttribute(relAttr); | 
 |             if (!enabledViaScript && sheet && !title.isEmpty()) { | 
 |                 // Yes, we have a title. | 
 |                 if (collections->preferredStylesheetSetName().isEmpty()) { | 
 |                     // No preferred set has been established. If | 
 |                     // we are NOT an alternate sheet, then establish | 
 |                     // us as the preferred set. Otherwise, just ignore | 
 |                     // this sheet. | 
 |                     if (e->hasLocalName(styleTag) || !rel.contains("alternate")) { | 
 |                         collections->setPreferredStylesheetSetName(title); | 
 |                         collections->setSelectedStylesheetSetName(title); | 
 |                     } | 
 |                 } | 
 |                 if (title != collections->preferredStylesheetSetName()) | 
 |                     activeSheet = 0; | 
 |             } | 
 |  | 
 |             if (rel.contains("alternate") && title.isEmpty()) | 
 |                 activeSheet = 0; | 
 |         } | 
 |         if (sheet) | 
 |             styleSheets.append(sheet); | 
 |         if (activeSheet) | 
 |             activeSheets.append(activeSheet); | 
 |     } | 
 | } | 
 |  | 
 | StyleSheetCollection::StyleResolverUpdateType StyleSheetCollection::compareStyleSheets(const Vector<RefPtr<CSSStyleSheet> >& oldStyleSheets, const Vector<RefPtr<CSSStyleSheet> >& newStylesheets, Vector<StyleSheetContents*>& addedSheets) | 
 | { | 
 |     // Find out which stylesheets are new. | 
 |     unsigned newStylesheetCount = newStylesheets.size(); | 
 |     unsigned oldStylesheetCount = oldStyleSheets.size(); | 
 |     if (newStylesheetCount < oldStylesheetCount) | 
 |         return Reconstruct; | 
 |  | 
 |     unsigned newIndex = 0; | 
 |     for (unsigned oldIndex = 0; oldIndex < oldStylesheetCount; ++oldIndex) { | 
 |         if (newIndex >= newStylesheetCount) | 
 |             return Reconstruct; | 
 |         while (oldStyleSheets[oldIndex] != newStylesheets[newIndex]) { | 
 |             addedSheets.append(newStylesheets[newIndex]->contents()); | 
 |             ++newIndex; | 
 |             if (newIndex == newStylesheetCount) | 
 |                 return Reconstruct; | 
 |         } | 
 |         ++newIndex; | 
 |     } | 
 |     bool hasInsertions = !addedSheets.isEmpty(); | 
 |     while (newIndex < newStylesheetCount) { | 
 |         addedSheets.append(newStylesheets[newIndex]->contents()); | 
 |         ++newIndex; | 
 |     } | 
 |     // If all new sheets were added at the end of the list we can just add them to existing StyleResolver. | 
 |     // If there were insertions we need to re-add all the stylesheets so rules are ordered correctly. | 
 |     return hasInsertions ? Reset : Additive; | 
 | } | 
 |  | 
 | bool StyleSheetCollection::activeLoadingStyleSheetLoaded(const Vector<RefPtr<CSSStyleSheet> >& newStyleSheets) | 
 | { | 
 |     // StyleSheets of <style> elements that @import stylesheets are active but loading. We need to trigger a full recalc when such loads are done. | 
 |     bool hasActiveLoadingStylesheet = false; | 
 |     unsigned newStylesheetCount = newStyleSheets.size(); | 
 |     for (unsigned i = 0; i < newStylesheetCount; ++i) { | 
 |         if (newStyleSheets[i]->isLoading()) | 
 |             hasActiveLoadingStylesheet = true; | 
 |     } | 
 |     if (m_hadActiveLoadingStylesheet && !hasActiveLoadingStylesheet) { | 
 |         m_hadActiveLoadingStylesheet = false; | 
 |         return true; | 
 |     } | 
 |     m_hadActiveLoadingStylesheet = hasActiveLoadingStylesheet; | 
 |     return false; | 
 | } | 
 |  | 
 | void StyleSheetCollection::analyzeStyleSheetChange(StyleResolverUpdateMode updateMode, const Vector<RefPtr<CSSStyleSheet> >& oldStyleSheets, const Vector<RefPtr<CSSStyleSheet> >& newStyleSheets, StyleResolverUpdateType& styleResolverUpdateType, bool& requiresFullStyleRecalc) | 
 | { | 
 |     styleResolverUpdateType = Reconstruct; | 
 |     requiresFullStyleRecalc = true; | 
 |  | 
 |     if (activeLoadingStyleSheetLoaded(newStyleSheets)) | 
 |         return; | 
 |  | 
 |     if (updateMode != AnalyzedStyleUpdate) | 
 |         return; | 
 |     if (!document()->styleResolverIfExists()) | 
 |         return; | 
 |  | 
 |     // Find out which stylesheets are new. | 
 |     Vector<StyleSheetContents*> addedSheets; | 
 |     styleResolverUpdateType = compareStyleSheets(oldStyleSheets, newStyleSheets, addedSheets); | 
 |  | 
 |     // If we are already parsing the body and so may have significant amount of elements, put some effort into trying to avoid style recalcs. | 
 |     if (!document()->body() || document()->hasNodesWithPlaceholderStyle()) | 
 |         return; | 
 |     StyleInvalidationAnalysis invalidationAnalysis(addedSheets); | 
 |     if (invalidationAnalysis.dirtiesAllStyle()) | 
 |         return; | 
 |     invalidationAnalysis.invalidateStyle(document()); | 
 |     requiresFullStyleRecalc = false; | 
 | } | 
 |  | 
 | static void collectActiveCSSStyleSheetsFromSeamlessParents(Vector<RefPtr<CSSStyleSheet> >& sheets, Document* document) | 
 | { | 
 |     HTMLIFrameElement* seamlessParentIFrame = document->seamlessParentIFrame(); | 
 |     if (!seamlessParentIFrame) | 
 |         return; | 
 |     sheets.append(seamlessParentIFrame->document()->styleSheetCollection()->activeAuthorStyleSheets()); | 
 | } | 
 |  | 
 | bool StyleSheetCollection::updateActiveStyleSheets(DocumentStyleSheetCollection* collections, StyleResolverUpdateMode updateMode, StyleResolverUpdateType& styleResolverUpdateType) | 
 | { | 
 |     Vector<RefPtr<StyleSheet> > styleSheets; | 
 |     Vector<RefPtr<CSSStyleSheet> > activeCSSStyleSheets; | 
 |     activeCSSStyleSheets.append(collections->injectedAuthorStyleSheets()); | 
 |     activeCSSStyleSheets.append(collections->documentAuthorStyleSheets()); | 
 |     collectActiveCSSStyleSheetsFromSeamlessParents(activeCSSStyleSheets, document()); | 
 |     collectStyleSheets(collections, styleSheets, activeCSSStyleSheets); | 
 |  | 
 |     bool requiresFullStyleRecalc; | 
 |     analyzeStyleSheetChange(updateMode, activeAuthorStyleSheets(), activeCSSStyleSheets, styleResolverUpdateType, requiresFullStyleRecalc); | 
 |  | 
 |     if (styleResolverUpdateType == Reconstruct) { | 
 |         document()->clearStyleResolver(); | 
 |     } else { | 
 |         StyleResolver* styleResolver = document()->styleResolver(); | 
 |         styleResolver->setBuildScopedStyleTreeInDocumentOrder(!scopingNodesForStyleScoped()); | 
 |         if (styleResolverUpdateType == Reset) { | 
 |             if (DocumentOrderedList* styleScopedScopingNodes = scopingNodesForStyleScoped()) { | 
 |                 for (DocumentOrderedList::iterator it = styleScopedScopingNodes->begin(); it != styleScopedScopingNodes->end(); ++it) | 
 |                     styleResolver->resetAuthorStyle(toContainerNode(*it)); | 
 |             } | 
 |             if (ListHashSet<Node*, 4>* removedNodes = scopingNodesRemoved()) { | 
 |                 for (ListHashSet<Node*, 4>::iterator it = removedNodes->begin(); it != removedNodes->end(); ++it) | 
 |                     styleResolver->resetAuthorStyle(toContainerNode(*it)); | 
 |             } | 
 |             ASSERT(m_treeScope->rootNode() == document()); | 
 |             styleResolver->resetAuthorStyle(toContainerNode(m_treeScope->rootNode())); | 
 |             styleResolver->appendAuthorStyleSheets(0, activeCSSStyleSheets); | 
 |         } else { | 
 |             ASSERT(styleResolverUpdateType == Additive); | 
 |             styleResolver->appendAuthorStyleSheets(m_activeAuthorStyleSheets.size(), activeCSSStyleSheets); | 
 |         } | 
 |     } | 
 |     m_scopingNodesForStyleScoped.didRemoveScopingNodes(); | 
 |     m_activeAuthorStyleSheets.swap(activeCSSStyleSheets); | 
 |     m_styleSheetsForStyleSheetList.swap(styleSheets); | 
 |  | 
 |     return requiresFullStyleRecalc; | 
 | } | 
 |  | 
 | } |